class Student:
    def __init__(self, xuehao, yuwen, shuxue, yingyu):
        self.xuehao = int(xuehao)
        self.yuwen = float(yuwen)
        self.shuxue = float(shuxue)
        self.yingyu = float(yingyu)
        self.pingjunshu = 0
        self.zong=0
        self.next = None